Pulverulent mortar composition having improved adhesion

ABSTRACT

Pulverulent mortar composition comprising a mineral binder, an inert material in the form of aggregate capable of being agglomerated in aqueous phase by means of said binder, and 0.2 to 1% of a fluid additive comprising 25 to 100% of a linear or branched, saturated or unsaturated hydrocarbon compound (i) which is liquid at room temperature and which includes one or more —COO— ester groups, the total weight of which, relative to the molar mass of said compound, is between 20 and 50%. Use for preparing an adhesive mortar for fixing ceramic tiles.

The present invention relates to a pulverulent mortar compositionintended in particular for use as tiling cement, which enables improvedadhesion characteristics to be obtained for cemented ceramic tiles,especially after contact with water, while exhibiting a reduced amountof inhalable dusts.

Mortars intended for use as tiling cement are also called adhesivemortars. They are well known and are widely used for fixing tiling (alsoreferred to as ceramic tiles or coatings) to both horizontal (grounds orscreeds) and vertical (walls and partitions) substrates, either on theinterior or exterior of dwellings. They take the form of powder andcomprise various ingredients, especially:

-   -   binders, and    -   granules of inert materials which can be agglomerated in aqueous        phase by means of said binders to form an aggregate.

The binders employed may be inorganic or organic.

Inorganic binders include hydraulic binders (that is, binders which areinsoluble in water and which set and harden by chemical reaction withwater) and also nonhydraulic binders (in other words, binders which aresoluble in water and which harden by drying).

Hydraulic inorganic binders include the following:

-   -   cements, such as Portland cement, composite cements (a mixture        of Portland cement with another product such as blast furnace        slag, fly ash, calcined shales, limestone, metakaolin),        high-alumina cements, and sulfoaluminate cements;    -   hydraulic lime.

Nonhydraulic inorganic binders include rich lime and sulfates such asgypsum, plaster, and anhydrite.

The organic binders are generally based on resins of animal or vegetableorigin or, more usually, on synthetic resins.

Examples that may be given of granules of inert materials include thefollowing: sand (especially silica sand or limestone sand), stonechippings, expanded clay, pozzolan, glass beads, barytes, hematites,slags, or else ground brick or ground concrete.

The powder form adopted by a mortar, especially an adhesive mortar, isobtained industrially by simple mixing of its various ingredients, whichare themselves generally in the form of solids in a pulverulent state.This powder is employed, in use, by blending with water (also referredto as mixing). The resulting product has a uniform, plastic appearance,and a consistency which allows it, in the case of an adhesive mortar, tobe spread over the substrate to be tiled and/or over the back of thetiles (using a trowel and/or a toothed spatula), to give an even layerwith a thickness of several millimeters that joins the ceramic tiles tothe substrate, resulting in a cohesive assembly which is stable overtime.

The solid particles which make up the mortars have a size which mayrange from around ten to several hundred micrometers and in some casesmay be capable of producing emission of dusts, in suspension in the air,which are potentially inhalable. This emission of inhalable dusts, whichmay take place both at the stage of industrial manufacture and at thetime of handling of the product by the user, before and during mixingwith water, is a disadvantage of mortars, particularly of adhesivemortars, that gives rise to workplace hygiene problems and is thesubject of regulation relating to employee protection.

Patent application WO 2006/084588 relates to the problem of reducingdust emissions during the handling of cement-based or hydraulicallysetting pulverulent materials. For that purpose it teaches the use ofhydrocarbons or mixtures of hydrocarbons, especially liquidhydrocarbons, and preferably of saturated aliphatic hydrocarbons such asmineral oils.

International application WO 2007/051817 recommends the incorporationinto the mortar composition of a fluid additive composed of at least oneapolar organic hydrocarbon substance selected from mineral oils,paraffinic oils, paraffins, or polyolefins. According to thisapplication, the incorporation of said fluid additive into the mortarcomposition does not give rise to any impairment of its physicochemicalcharacteristics, including the adhesion characteristics.

Adhesion characteristics feature at the forefront of the end performanceattributes expected from adhesive mortars for tiling (or ceramiccoatings). These features are generally quantified by determining themaximum breaking stresses, which are measured by removal resistancetests carried out on tiles cemented to a concrete slab under standardconditions, in accordance with European standard EN 1348. These testsmay be carried out on an assembly which, after being produced, has beenfirst of all:

-   -   either simply stored for approximately 1 month at ambient        temperature (for measuring the dry adhesion),    -   or immersed in water for 3 weeks (for measuring the adhesion        after water contact).

The determination of the adhesion after water contact is particularlyimportant in evaluating the stability of the assembly that results fromthe bonding of a ceramic coating to an exterior substrate of a dwelling,which is therefore exposed to the weather: this tiled substrate may be,for example, a tiled facade or tiled patio, or else tiling intended forcoating a swimming pool.

In contrast to the teaching of document WO 2007/051817, the applicanthas now found, on the basis of a large number of tests, that the effectof introducing an apolar organic hydrocarbon substance, such as ahydrocarbon oil, into an adhesive mortar is to reduce the adhesion, andmore particularly the adhesion after water contact.

The aim of the present invention is to provide a pulverulent mortarcomposition, which can be used in particular as an adhesive mortar, andwhich comprises a fluid additive which lowers the emission of inhalabledusts by the composition, and which offers, moreover, excellent dryadhesion performance and, more particularly, adhesion performance afterwater contact.

The invention accordingly provides a pulverulent mortar compositionwhich comprises:

-   -   from 10% to 60% of an inorganic binder,    -   from 40% to 90% of an inert material in granule form that can be        agglomerated in aqueous phase by means of said binder,    -   from 0.2% to 1% of a fluid additive comprising from 25% to 100%        of a saturated or unsaturated, linear or branched hydrocarbon        compound (i) which is liquid at ambient temperature and which        includes one or more ester groups —COO— of which the total        weight, relative to the molar mass of said compound (i), is        between 20% and 50%.

It has been found that the selection of this specific polar organiccompound leads to an adhesive mortar which, in addition to reducedemission of inhalable dusts, possesses high performance properties interms of adhesion, and especially of adhesion after water contact.Advantageously, the adhesion after water contact is maintained at a veryhigh level, greater than or equal to 0.95 MPa.

In the absence of indications to the contrary, it is specified that thepercentages used in the present text to quantify the amount ofcomponents in the composition according to the invention or of the fluidadditive are weight/weight percentages. Also, the indefinite article “a”or “an”, used to denote the components of said composition or saidadditive, should be understood to mean “one or more” components.

The inorganic, hydraulic or nonhydraulic, binder employed in the mortarcomposition according to the invention may be selected from thoserecited above, either alone or as a mixture.

The granules of inert material may also be selected from the materialsrecited above, alone or in a mixture.

As inorganic binder it is preferred to use cement, and more preferablyPortland cement and/or high-alumina cement, and as granules of inertmaterial it is preferred to use sand, especially silica sand orlimestone sand.

The compound (i) included in the fluid additive incorporated into thepulverulent composition according to the invention is preferably amono-, di-, tri- or tetra-ester (or a mixture of such compounds), whichin the remainder of the present text is referred to by the term “esteroil”.

According to one preferred variant of the composition according to theinvention, the compound (i) is selected from the group consisting of:

-   -   (a) mono-esters of formula:

R²—A—R²  (I)

in which:

-   -   R⁴ and R² are identical or different and represent a saturated        or unsaturated, linear or branched hydrocarbon radical which        contains from 1 to 10 carbon atoms and is optionally substituted        by an —OH or —SH group;    -   A represents an ester group of formula —(CO)O— or —O(CO)—;    -   (b) di-esters of formula:

R³—A^(l)—R⁴—A²—R⁵  (II)

in which:

-   -   R³ and R⁵ are identical or different and represent a saturated        or unsaturated, linear or branched hydrocarbon radical which        contains from 1 to 20 carbon atoms and is optionally substituted        by an —OH or —SH group;    -   R⁴ is a divalent radical deriving from the monovalent radical        having the same meaning as radicals R³ or R⁵ defined above;    -   A^(l) and A² are identical or different and have the same        meaning as the radical A defined above;    -   (c) tri-esters obtained by condensing:        -   a saturated or unsaturated, linear or branched carboxylic            acid which contains from 2 to 20 carbon atoms and is            optionally substituted by an —OH or —SH group, with        -   a saturated or unsaturated, linear or branched hydrocarbon            compound which contains from 3 to carbon atoms, of which 3            separate atoms are each bonded to an —OH group; and    -   (d) tetra-esters obtained by condensing:        -   a saturated or unsaturated, linear or branched carboxylic            acid which contains from 2 to 20 carbon atoms and is            optionally substituted by an —OH or —SH group, with        -   a saturated or unsaturated, linear or branched hydrocarbon            compound which contains from 4 to 10 carbon atoms, of which            4 separate atoms are each bonded to an —OH group.

Examples that may be given of compounds (i) are the following compounds,which are widely available commercially:

-   -   as mono-ester: 2-ethylhexyl lactate (also called 2-ethylhexyl        2-hydroxypropanoate) of formula:

H₃C—CH(OH)—CO—OCH₂—CH(C₂H₅)[(CH₂)₃—CH₃]

-   -   (molar weight of the —COO— group: 22%)    -   as di-ester:    -   the diethyl ester of adipic acid (or diethyl adipate), of        formula:

EtOCO—(CH₂)₄—COOEt (molar weight of the —COO— group: 43%)

-   -   the diisobutyl ester of adipic acid (or diisobutyl adipate), of        formula:

iBuOCO—(CH₂)₄—COOiBu (molar weight of the —COO— group: 34%)

-   -   as tri-ester, the glycerol triester of capric acid (or glycerol        tricaprylate), of formula:

[(C₉H₁₉)COO]CH₂—CH[OCO(C₉H₁₉)]—CH₂[OCO(C₉H₁₉)]

-   -   (molar weight of the —COO— group: 24%)    -   as tetra-ester, the pentaerythritol tetraester of capric acid        (or pentaerythritol tetracaprylate), of formula:

C(CH₂—OCO—C₉H₁₉)₄ (molar weight of the —COO— group: 23%).

A polar organic compound (i) including one or more ester groups for atotal weight of between 30% and 50% is more particularly preferred, suchas diethyl and/or diisobutyl adipate.

According to one variant of the composition according to the invention,the fluid additive may comprise, further to the 25% to 100% of theaforementioned polar organic compound (i), from 0% to 75% of an apolarorganic compound (ii) which is liquid at ambient temperature. Saidcompound (ii) is generally selected from mineral oils, paraffinic oils,polyolefins, or mixtures of these substances. It is referred tohereinafter as “hydrocarbon oil”. Examples of commercial productscovered by (ii) include the following:

-   -   Lytol and Semtol 70/28, which are white mineral oils sold by        Sonneborn, having respective viscosities (measured at 23° C. by        a Brookfield viscometer fitted with spindle 2V100, in accordance        with standard ASTM D 445) as follows: 28 and 56 mPa.s.    -   Hydroseal G3H (from Total), which is a mixture of hydrotreated        petroleum middle distillates having a viscosity (measured under        the same conditions as above) of 24 mPa.s.    -   Nexbase® 2002 (Neste Oil), which is a synthetic oil consisting        essentially of hydrogenated, dimerized 1-decene.

Whereas the introduction into an adhesive mortar composition of a fluidadditive consisting exclusively of the compound (ii) results in adecrease in the adhesion characteristics, the introduction of thecompound (i) or of a mixture thereof with the compound (ii) in theproportions indicated advantageously allows the adhesion performances tobe maintained, including the adhesion after water contact, at a veryhigh level, preferably greater than or equal to 0.95 MPa.

According to one preferred variant of the invention, the compositioncomprises from 20% to 40% of the inorganic binder and from 60% to 70% ofthe inert material in granule form.

According to another preferred variant of the invention, the fluidadditive is present in the mortar composition at from 0.3% to 0.6%.

A preferred composition according to the invention is one which furthercomprises, as organic binder, from 1% to 10%, preferably 2% to 7%, of acopolymer comprising one (or more) vinyl ester(s) and optionally amaleic ester. Products of these kinds are presently availablecommercially, often in a mixture with inert fillers, such as, forexample, Axilat™ UP 620E (approximately 90% by weight of copolymer ofvinyl acetate, vinyl versatate, and maleic ester) and Axilat™ PAV 51(approximately 90% by weight of copolymer of vinyl acetate and vinylversatate), from Hexion.

According to one variant of the composition according to the invention,which is particularly preferred for its high adhesion performance, thecomposition comprises from 5% to 6% of copolymer of vinyl acetate, vinylversatate, and maleic ester.

The mortar composition according to the invention may also compriseingredients which are known in the art, such as:

-   -   limestone, dolomite and/or silica fillers in the form of        particles with a size of less than 50 μm, in an amount of from        0% to 25%, preferably from 2% to 15%;    -   a rheological agent and/or water retainer, such as a cellulose        ether, a guar gum or starch derivative, or else cellulose        fibers, in an amount of from 0.3% to 1%, preferably from 0.3% to        0.7%;    -   a (setting or hardening) accelerator, based for example on        chloride or formate salts, in an amount of from 0.2% to 4%,        preferably from 0.3% to 2%.

The mortar composition according to the invention is produced by simplemixing of the solid pulverulent ingredients and addition of the fluidadditive by spraying.

The present invention also relates to the use of the mortar compositionas defined above for mixing thereof with water, for the purpose ofproducing a mortar, a spackling or wall coating, a grout, orcement-based products used in construction.

Use for the purpose of producing an adhesive mortar for fixing ceramictiles is especially preferred.

The examples which follow are given purely by way of illustration of theinvention and should not be construed as limiting the scope thereof.

Example A (Reference): Adhesive Mortar Composition without FluidAdditive

A pulverulent adhesive mortar composition A is prepared by simple drymixing of the following ingredients:

-   -   30% of standardized Portland cement PC CEM I 52.5 N    -   63.6% of silica sand with a grain size of less than 500 μm    -   3% of a limestone filler with a size of less than 50 μm    -   2.4% of Axilat™ UP 620E    -   0.6% of an accelerator    -   0.4% of a rheological agent and/or water retainer.

The adhesion characteristics of the adhesive mortar A are determined bythe adhesion test described below.

Adhesion Test:

The adhesive mortar composition is mixed with water, in a proportion ofapproximately 25 g of water to 100 g of powder, for 90 seconds.

Then, after a rest time of 5 minutes and homogenization with a spatula,the mixture is applied to 2 identical substrates each consisting of asquare concrete slab with sides measuring 40 cm and a thickness of 4 cm,to form a thin layer which is suitably grooved by means of a notchedspatula, its thickness being between 2 and 6 mm.

10 dry-pressed sandstone tiles with a side length of 5 cm and athickness of 5 mm are subsequently placed onto each slab thus coatedwith adhesive, held in a horizontal position, and spaced apart by 5 cm.Each tile is then applied to the slab using a pressure resulting fromthe application of a 2 kg weight for 30 seconds.

The 2 resulting assemblies are subjected to the following storageconditions:

-   -   one is left for 28 days at 23° C. and 50% relative humidity, for        determination of the dry adhesion;    -   the other is left for 7 days at 23° C. and 50% relative        humidity, then immersed for 21 days in water at 23° C., for        determination of the adhesion after water contact.

At the end of this storage, for each tile of the two aforementionedassemblies, a measurement is made of the force required to remove saidtile from the concrete slab. For this purpose, metal tension elementswith a square face having a side length of 5 cm are affixed to each tileby means of a high-strength epoxide-type structural adhesive. Eachelement is then connected to a tensile apparatus which is capable ofapplying to said element a tensile force which increases (until removalof the tile) at a constant rate of approximately 250 N/s.

The dry adhesion and the adhesion after water contact are obtained byrelating the removal force measured for each of the 10 tiles to thesurface area of a tile, then by calculating the average for each of the2 corresponding assemblies. The 2 results are expressed in MPa and aregiven in Table 1.

For further details, reference is made to European standard EN 1348.

Examples A1-A4 (Reference) : Effect of Adding 0.3% of a Hydrocarbon Oilon the Adhesion of Adhesive Mortar A

Example A is repeated, adding 0.3% by weight of the hydrocarbon oilindicated in Table 1 to the pulverulent composition by spraying.

The adhesion results likewise indicated in Table 1 are obtained.

Example B (Reference): Adhesive Mortar Composition without FluidAdditive

Example A is repeated, replacing composition A by composition B below:

-   -   30% of standardized Portland cement PC CEM I 52.5 N    -   62.6% of silica sand with a grain size of less than 500 μm    -   3% of a limestone filler with a size of less than 50 μm    -   3% of Axilat™ UP 620E    -   0.7% of a rheological agent and/or water retainer    -   0.7% of an accelerator

The adhesion results likewise indicated in Table 1 are obtained.

Examples B1-B3 (Reference) : Effect of Adding 0.6% of a Hydrocarbon Oilon the Adhesion of Adhesive Mortar B

Example B is repeated, adding 0.6% by weight of the hydrocarbon oilindicated in Table 1 to the pulverulent composition.

The adhesion results likewise indicated in Table 1 are obtained.

Example C (Reference): Adhesive Mortar Composition without FluidAdditive

Example A is repeated, replacing composition A by composition C below:

-   -   30% of standardized Portland cement PC CEM I 52.5 N    -   59.9% of silica sand with a grain size of less than 500 μm    -   3% of a limestone filler with a size of less than 50 μm    -   6% of Axilat™ UP 620E    -   0.7% of a rheological agent and/or water retainer    -   0.4% of an accelerator

The adhesion results likewise indicated in Table 1 are obtained.

Examples C1-C3 (Reference) : Effect of Adding 0.6% of a Hydrocarbon Oilon the Adhesion of Adhesive Mortar C

Example C is repeated, adding 0.6% by weight of the hydrocarbon oilindicated in Table 1 to the pulverulent composition.

The adhesion results likewise indicated in Table 1 are obtained.

Table 1, for the 3 adhesive mortars A, B, and C, shows a reduction inadhesion after water contact, resulting from the addition of 0.3% to0.6% of the hydrocarbon oil indicated.

Examples 1 and 2: Effect of Adding 0.3% or 0.6% of an Ester Oil (i) onthe Adhesion of Adhesive Mortar B

Example B is repeated, adding 0.3% or 0.6% by weight of diethyl adipateto the composition by spraying, as indicated in Table 2.

The adhesion results indicated in Table 2 are obtained.

Examples 3 to 8: Effect of Adding 0.3% or 0.6% of an Ester Oil (i) onthe Adhesion of Adhesive Mortar C

Example C is repeated, adding 0.3% or 0.6% of the ester oil (i) to thepulverulent composition as fluid additive, indicated in Table 2.

The adhesion results likewise indicated in Table 2 are obtained.

Examples 9 to 17: Effect of Adding 0.6% of a Fluid Additive Consistingof a Mixture of Ester Oil and Hydrocarbon Oil on the Adhesion ofAdhesive Mortar C

Example C is repeated, adding 0.6% of a fluid additive consisting of amixture of (i) and (ii), in the percentages indicated in Table 3, to thepulverulent composition.

The adhesion results likewise indicated in Table 3 are obtained.

Compositions 1 to 17 according to the invention provide excellent dryadhesion performance, greater than that of the correspondingcompositions without fluid additive (reference compositions B and C).They also produce an adhesion after water contact which is maintainedsubstantially at the level of that provided by the referencecompositions B and C, and especially greater than or equal to 0.95 MPa.

The emission of inhalable dusts by these same compositions 1 to 17 wasevaluated visually relative to the reference compositions without fluidadditive B and C: dust emission was found to be significantly reduced.

TABLE 1 Example A A1 A2 A3 A4 B B1 B2 B3 C C1 C2 C3 Adhesive mortar A AA A A B B B B C C C C Amount of Hydroseal — 0.3 — — — — 0.6 — — — 0.6 —— hydrocarbon G3H oil (in %) Semtol 70/28 — — 0.3 — — — — 0.6 — — — 0.6— Nexbase 2002 — — — 0.3 — — — — — — — — — Lytol — — — — 0.3 — — — 0.6 —— — 0.6 Adhesion Dry 1.00 0.96 1.00 0.89 1.04 1.00 0.84 0.85 0.73 1.000.99 1.02 1.04 (in MPa) adhesion Adhesion after 1.00 0.81 0.90 0.76 0.811.00 0.60 0.66 0.60 1.00 0.84 0.76 0.90 water contact

TABLE 2 Example B 1 2 C 3 4 5 6 7 8 Adhesive mortar B B B C C C C C C CAmount of fluid additive (in %) 0 0.3 0.6 0 0.6 0.3 0.6 0.6 0.6 0.6Amount of 2-Ethylhexyl — — — — 100 — — — — — ester oil (i) lactate inthe fluid Diethyl — 100 100 — — 100 100 — — — additive adipate (in %)Diisobutyl — — — — — — — 100 — — adipate Glycerol — — — — — — — — 100 —tricaprylate Pentaerythritol — — — — — — — — — 100 tetracaprylateAdhesion Dry 1.00 1.01 1.42 1.00 1.35 1.43 1.65 1.44 1.50 1.26 (in MPa)adhesion Adhesion after 1.00 0.96 1.01 1.00 1.14 1.02 1.09 1.03 1.021.00 water contact

TABLE 3 Example C 9 10 11 12 13 14 15 16 17 Adhesive mortar C C C C C CC C C C Amount of fluid additive (in %) 0 0.6 0.6 0.6 0.6 0.6 0.6 0.60.6 0.6 Amount of Diethyl — 70 70 70 50 50 50 30 30 30 ester oil (i)adipate in the fluid additive (in %) Amount of Hydroseal — 30 — — 50 — —70 — — hydrocarbon G3H oil (ii) in the Semtol 70/28 — — 30 — — 50 — — 70— fluid addi- Lytol — — — 30 — — 50 — — 70 tive (in %) Adhesion Dry 1.001.48 1.34 1.39 1.35 1.34 1.33 1.15 1.41 1.31 (MPa) adhesion Adhesionafter 1.00 1.07 1.08 1.00 1.03 0.95 0.97 1.03 0.99 1.06 water contact

1. A pulverulent mortar composition which comprises: from 10% to 60% ofan inorganic binder, from 40% to 90% of an inert material in granuleform that can be agglomerated in aqueous phase by means of said binder,from 0.2% to 1% of a fluid additive comprising from 25% to 100% of asaturated or unsaturated, linear or branched hydrocarbon compound (i)which is liquid at ambient temperature and which includes one or moreester groups —COO— of which the total weight, relative to the molar massof said compound (i), is between 20% and 50%.
 2. The pulverulent mortarcomposition as claimed in claim 1, characterized in that cement is usedas inorganic binder and sand is used as granules of inert material. 3.The pulverulent mortar composition as claimed in claim 1, characterizedin that the compound (i) is a mono-, di-, tri- or tetra-ester.
 4. Thepulverulent mortar composition as claimed in claim 1, characterized inthat the compound (i) is selected from the group consisting of: (a)mono-esters of formula:R¹—A—R²  (I) in which: R¹ and R² are identical or different andrepresent a saturated or unsaturated, linear or branched hydrocarbonradical which contains from 1 to 10 carbon atoms and is optionallysubstituted by an —OH or —SH group; A represents an ester group offormula —(CO)O— or —O(CO)—; (b) di-esters of formula:R³—A¹—R⁴—A²—R⁵  (II) in which: R³ and R⁵ are identical or different andrepresent a saturated or unsaturated, linear or branched hydrocarbonradical which contains from 1 to 20 carbon atoms and is optionallysubstituted by an —OH or —SH group; R⁴ is a divalent radical derivingfrom the monovalent radical having the same meaning as radicals R³ or R⁵defined above; A^(l) and A² are identical or different and have the samemeaning as the radical A defined above; (c) tri-esters obtained bycondensing: a saturated or unsaturated, linear or branched carboxylicacid which contains from 2 to 20 carbon atoms and is optionallysubstituted by an —OH or —SH group, with a saturated or unsaturated,linear or branched hydrocarbon compound which contains from 3 to 10carbon atoms, of which 3 separate atoms are each bonded to an —OH group;and (d) tetra-esters obtained by condensing: a saturated or unsaturated,linear or branched carboxylic acid which contains from 2 to 20 carbonatoms and is optionally substituted by an —OH or —SH group, with asaturated or unsaturated, linear or branched hydrocarbon compound whichcontains from 4 to 10 carbon atoms, of which 4 separate atoms are eachbonded to an —OH group.
 5. The pulverulent mortar composition as claimedin claim 1, characterized in that the polar organic compound (i)includes one or more ester groups for a total weight of between 30% and50%.
 6. The pulverulent mortar composition as claimed in claim 1,characterized in that the fluid additive further comprises from 0% to75% of an apolar organic compound (ii) which is liquid at ambienttemperature.
 7. The pulverulent mortar composition as claimed in claim6, characterized in that the compound (ii) is selected from mineraloils, paraffinic oils, polyolefins, or mixtures of these substances. 8.The pulverulent mortar composition as claimed in claim 1, characterizedin that it comprises from 20% to 40% of the inorganic binder and from60% to 70% of the inert material in granule form.
 9. The pulverulentmortar composition as claimed in claim 1, characterized in that itcomprises the fluid additive at from 0.3% to 0.6%.
 10. The pulverulentmortar composition as claimed in claim 1, characterized in that itfurther comprises, as organic binder, from 1% to 10% of a copolymercomprising one (or more) vinyl ester(s).
 11. The pulverulent mortarcomposition as claimed in claim 10, characterized in that the organicbinder is a copolymer of vinyl acetate, vinyl versatate, and maleicester, present at from 5% to 6%.
 12. A process for producing a mortar, aspackling, a wall coating, a grout, a cement-based product used inconstruction or an adhesive mortar for fixing ceramic tiles, comprisingmixing water and a mortar composition according to claim
 1. 13.(canceled)
 14. A mortar, spackling, wall coating, grout, cement-basedproduct, or adhesive mortar comprising a mortar composition according toclaim 1.